Dendritic cells tell the immune system what to attack
Scientists may be one step closer to producing a specific targeted vaccine for killing cancer cells.
UK researchers have pinpointed a protein on immune cells which they hope will help them harness the body's defences to attack a tumour.
A vaccine designed to "home in" on the protein would deliver a message to the immune system to attack the invading cancer, they said.
The research is published in the Journal of Clinical Investigation.
The protein is unique to a type of immune cell called a dendritic cell, which is responsible for triggering the body's defence system.
Its job is to present pathogens or foreign molecules to other cells of the immune system, which in turn eliminate them.
The team at Cancer Research UK's London Research Institute said scientists have been searching for proteins or "tags" on dendritic cells for over 30 years.
In theory a vaccine carrying a foreign molecule from a cancer cell could be targeted to the dendritic cells, which would then prompt the immune system to attack the "invading" cancer. The same approach could be used for treating HIV or malaria, the researchers said.
T cell army
Study leader Dr Caetano Reis e Sousa said the team had found a unique protein called DNGR-1, which could be used to deliver such a vaccine to the door of the dendritic cell.
"Vaccines work by triggering an army of immune cells, called T cells, to attack potentially dangerous foreign molecules, like those found on pathogens.
"Dendritic cells are the messengers, telling the T cells who to attack.
"Vaccines will carry a sample of the offending molecule and deliver it to DNGR-1 on the dendritic cells, which in turn will present the molecule to the armies of T cells and instruct them to attack."
Cancer Research UK's director of cancer information, Dr Lesley Walker, said: "Developing treatments that accurately target cancer and have few serious side-effects is one of Cancer Research UK's top goals.
"The results of this research are an important step towards understanding how to create targeted cancer vaccines in the future."